Yes, All documented vessels (registered with the U.S. Coast Guard) must be registered, but not titled. They must display a current boat sticker on the vessel. The current registration must be carried in the vessel when in operation.
710:22-1-12. Vessels registered with U.S. Coast Guard
[Source: Added at 8 Ok Reg 3301, eff 7-8-91 (emergency); Added at 9 Ok Reg 2149, eff 6-12-92]